Use the latest official ECJ 3.14.0 (appium#1024)

The old ECJ reference was bogus (see official confirmation: https://bugs.eclipse.org/bugs/show_bug.cgi?id=499019#c19) and didn't work properly with JDK9

Author: valfirst

build.gradle

@@ -36,7 +36,7 @@ configurations {
 }
 
 dependencies {
- ecj 'org.eclipse.jdt.core.compiler:ecj:4.6.1'
+ ecj 'org.eclipse.jdt:ecj:3.14.0'
 }
 
 compileJava {